Flux for solder for aluminum



UNITED STATES PATENT (mam.

JAMES G. KELLY, OF SEDALIA, MISSOURI, ASSIGNOR or ONE-HALF T0 HOLMESHALL, OF

SEDALIA, MISSOURI.

No Drawing.

T 0 all whom it may concern Be it known that I, J AMES G. KELLY, acitizen of the United States, residing at the city of Sedalia, in thecounty of Pettis and State of Missouri, have invented certain new anduseful Improvements in Fluxes for Solder for Aluminum, of which thefollowing is a specification.

This invention consists in an improvement in fluxes for solders foruniting aluminum, and can be used not only for uniting two parts bothmade of aluminum, but, also, two parts one of Which is aluminum and theother of some other material, -as, for instance, brass or copper.

Attempts have heretofore been made to produce a solder for joiningaluminum parts, but the results have not been satisfactory. Moreover, inusing prior aluminum solders it has been necessary to soak in a.suitable pickle the parts to be joined, which takes much time and delaysthe soldering process, besides involving the cost of the picklingmaterial. In some instances the parts to be joined by such prior soldershave been painted with a suitable acid preparatory to soldering.

In the use of the invention forming the subje t matter hereof, the partsdo not need to be prepared by either pickling or the use of acid. Allthat is necessary is that the adjoining ends or edges or parts shall bescraped clean with a suitable knife or scraper.

In using prior solders for aluminum, ithas been necessary to use theoxy-acetylene welding process, but the solder of this invention can beused with an ordinary soldering iron, preferably heated as hot aspossible, and preferably to a substantial extent hotter than when usedfor soldering tin.

The solder with which this flux is preferably to be used is'compoundedsubstantially as follows:

Fifteen ounces (15 oz.) of zinc, seventeen ounces (17 oz.) of lead, andseventeen ounces (17 oz.) of block tin are combined together by thefollowing process: First, the zinc is melted; then the lead is melted;and then the block tin is melted. Each is kept thoroughly stirred whilebeing melted. When the three ingredients have been melted, then they arethoroughly mixed together by stirring for about four (4) min-Specification of Letters Patent.

Patented Nov. 11 1919.

Application filed February 10, 1919. Serial N 0. 276.199. i/

utes. The mixture is then poured into a mold and allowed to harden.\Vhile the above is the preferred formula, yet the same has been usedwith the addition thereto of one ounce (1 oz.) of aluminum withsatisfactory results.

Whenit is desired to use this solder, the soldering-iron, heated asabove stated, is first rubbed over the parts to be united. Then theliereinafter-described flux is rubbed over the said parts. Then the hotsoldering-iron is rubbed on sal ammoniac. Then the above-describedaluminum solder is applied to the parts to be united with thesoldering-iron, used in the usual way, the said parts being kept wellfluxed during the soldering operation and the soldering-iron beingfrequently rubbed over the sal ammoniac during that operation, which iscontinued until the parts are thoroughly tinned or covered over withthis tllLll'l'llIlllIIl solder, after which common solder, such as usedin soldering tin, can be applied in the usual way, but using theabove-mentioned flux (hereinafter described) while doing so.

Of course, it is to be understood that the ordinary solder will notstick to aluminum,

but after the above-described aluminum solder has been applied toaluminum ordinary solder for tin will stick to it.

In use, a soldering-iron will be prepared in the usual manner by tinningthe same with this solder. After the iron has been thus tinned, thecleaned parts to be-joined are treated with the said flux and are sotinned with this solder by constantly rubbing with the iron, and theheat of the soldering iron is applied in the customary method ofsoldering to the strip or block of this solder, which is held ad acentto the joint to be made, and the union takes place.

If desired, a blow-pipe or oxy-acetylene welding apparatus may be usedafter the parts to be joined have been tinned as above described by theuse of the iron.

The method of melting this solder at the joint is the same as practisedwith any other solder. On account of the ingredicuts of this article andthe method in which they are combined together, the resultant joint isstronger than the aluminum itself.

,It is well known that lead will not unite the surface of aluminum forunion with lead where that is desired, in which use of this solder thealuminum is first tinned with this solder and thereupon ordinary softsolder can be used to form a union with the said tinned part of thealuminum article, there being no antipathy of the lead in the softsolder to union With this solder.

In this article the zinc is used for strength and the tin for its morereadily fusible quality.

The said flux may consist of skunk oil alone or of the same combinedWith melted mutton tallow or of skunk oil combined With stearic acid,the proportions being imma- 15 terial.

I claim:

1. A flux for an aluminum solder having skunk oil as the mainingredient.

2. A flux for aluminum solder made up 20 of skunk oil and melted muttontallow.

I testimony whereof I hereunto afiix my signature.

JAMES G. KELLY.

